Reconfigurable high-order mode pass filter for mode-division multiplexing

Prapty Saha; Oruni Aminul; Md Atiqur Rahman; Md Shah Alam; Kazi Tanvir Ahmmed

doi:10.1016/j.heliyon.2022.e11706

Reconfigurable high-order mode pass filter for mode-division multiplexing

Heliyon. 2022 Nov 18;8(11):e11706. doi: 10.1016/j.heliyon.2022.e11706. eCollection 2022 Nov.

Authors

Prapty Saha¹, Oruni Aminul¹, Md Atiqur Rahman¹, Md Shah Alam¹, Kazi Tanvir Ahmmed¹

Affiliation

¹ Department of Electrical and Electronic Engineering, University of Chittagong, Chittagong, 4331, Bangladesh.

Abstract

In mode division multiplexing (MDM) optical system, the mode filter has become an inseparable part to reduce modal crosstalk and transmit the desired modes unabatedly. As filtering out lower-order mode is difficult, here we propose a reconfigurable structure of a higher-order mode pass filter consisting of two tunable mode converters and a directional coupler (DC) in a three-mode planar waveguide platform. By switching the working states of the mode converters, the structure can also be used as a fundamental mode (TE₀) pass filter and hence dynamic output signals can be achieved. For the second-order mode (TE₂) transmission, the simulated excess loss is ∼0.61 dB at 1.550 μm and the extinction ratio remains ≥24 dB (power ratio of TE₀ & TE₂ Launch) and ≥25 dB (power ratio of TE₁ & TE₂ Launch) at the entire C-band (1.530-1.565 μm). The device has negligible polarization dependence and hence the TM polarization exhibits similar results.

Keywords: MZI device; Mode converter; Mode filter; Planar waveguide.